Search Publications
The Galactic warp revealed by Gaia DR2 kinematics
Bailer-Jones, C. A. L.; Fouesneau, M.; Andrae, R. +14 more
Using Gaia DR2 astrometry, we map the kinematic signature of the Galactic stellar warp out to a distance of 7 kpc from the Sun. Combining Gaia DR2 and 2-Micron All Sky Survey photometry, we identify, via a probabilistic approach, 599 494 upper main sequence (UMS) stars and 12 616 068 giants without the need for individual extinction estimates. The…
An overabundance of black hole X-ray binaries in the Galactic Centre from tidal captures
Metzger, B. D.; Generozov, A.; Stone, N. C. +1 more
A large population of X-ray binaries (XRBs) was recently discovered within the central parsec of the Galaxy by Hailey et al. While the presence of compact objects on this scale due to radial mass segregation is, in itself, unsurprising, the fraction of binaries would naively be expected to be small because of how easily primordial binaries are dis…
Radial distribution of stellar motions in Gaia DR2
Cropper, Mark; Grand, Robert J. J.; Seabroke, George +4 more
By taking advantage of the superb measurements of position and velocity for an unprecedented large number of stars provided in Gaia DR2, we have generated the first maps of the rotation velocity, Vrot, and vertical velocity, Vz, distributions as a function of the Galactocentric radius, Rgal, across a radial range o…
STREAMFINDER - I. A new algorithm for detecting stellar streams
Malhan, Khyati; Ibata, Rodrigo A.
We have designed a powerful new algorithm to detect stellar streams in an automated and systematic way. The algorithm, which we call the STREAMFINDER, is well suited for finding dynamically cold and thin stream structures that may lie along any simple or complex orbits in Galactic stellar surveys containing any combination of positional and kinema…
Density perturbations for running vacuum: a successful approach to structure formation and to the σ8-tension
Gómez-Valent, Adrià; Solà Peracaula, Joan
Recent studies suggest that dynamical dark energy (DDE) provides a better fit to the rising affluence of modern cosmological observations than the concordance model (ΛCDM) with a rigid cosmological constant, Λ. Such is the case with the running vacuum models (RVMs) and to some extent also with a simple XCDM parametrization. Apart from the cosmic m…
The magnetic early B-type stars I: magnetometry and rotation
Wade, G. A.; Neiner, C.; Shultz, M. E. +7 more
The rotational and magnetic properties of many magnetic hot stars are poorly characterized, therefore the Magnetism in Massive Stars and Binarity and Magnetic Interactions in various classes of Stars collaborations have collected extensive high-dispersion spectropolarimetric data sets of these targets. We present longitudinal magnetic field measur…
The SUrvey for Pulsars and Extragalactic Radio Bursts - I. Survey description and overview
Possenti, A.; Kramer, M.; Burgay, M. +19 more
We describe the Survey for Pulsars and Extragalactic Radio Bursts (SUPERB), an ongoing pulsar and fast transient survey using the Parkes radio telescope. SUPERB involves real-time acceleration searches for pulsars and single-pulse searches for pulsars and fast radio bursts. We report on the observational set-up, data analysis, multiwavelength/mess…
Analysis of the Herschel DEBRIS Sun-like star sample
Duchêne, G.; Lestrade, J. -F.; Wyatt, M. C. +4 more
This paper presents a study of circumstellar debris around Sun-like stars using data from the Herschel DEBRIS Key Programme. DEBRIS is an unbiased survey comprising the nearest ∼90 stars of each spectral type A-M. Analysis of the 275 F-K stars shows that excess emission from a debris disc was detected around 47 stars, giving a detection rate of 17…
Linking black hole growth with host galaxies: the accretion-stellar mass relation and its cosmic evolution
Brandt, W. N.; Vignali, C.; Xue, Y. Q. +9 more
Previous studies suggest that the growth of supermassive black holes (SMBHs) may be fundamentally related to host-galaxy stellar mass (M⋆). To investigate this SMBH growth-M⋆ relation in detail, we calculate long-term SMBH accretion rate as a function of M⋆ and redshift [\overlineBHAR(M_{\star }, z)] over ranges of…
Transient spiral structure and the disc velocity substructure in Gaia DR2
Bovy, Jo; Grand, Robert J. J.; Kawata, Daisuke +2 more
The second data release from ESA's Gaia mission has revealed many ridge-like structures in the velocity distribution of the Milky Way. We show that these can arise naturally from winding transient spiral structure that is commonly seen in N-body simulations of disc galaxies. We construct test particle models of the winding spiral structure, and co…